Possible Clues:

• Not, by the sound of it, the way you'd be paid by the day - with silver, perhaps
• Overturned the tin of salt at such a speed
• Tear tin up for fertiliser
• Egg - consider added salt
• Such speed might be lousy and salty
• Fertiliser - used within reason it rates very highly
• A fertiliser can put up value
• Such salt will give one lousy sort of speed
• What a lousy, salty sort of a spped!
• Off-peak price said to be for fertiliser